Dhaneesh Kumar Gopalakrishnan, PhD student, Monash University
The Kagome lattice in two-dimensional (2D) and layered materials hosts both Dirac-like and flat electronic bands, offering a rich space to realise strongly correlated electronic phases of matter. There is growing effort in the theoretical prediction and experimental realisation of these phenomena in organic and metal-organic nanomaterials using the versatile protocols of bottom-up self-assembly. Here we report the synthesis of a 2D metal-organic framework (MOF) with honeycomb-Kagome (HK) crystal structure via coordination of copper atoms with di-cyano-anthracene (DCA) molecules on a Ag(111) noble metal surface.
We directly observe Kondo screening of magnetic moments from unpaired electrons in the 2D MOF partially filled HK valence band via low-temperature scanning tunnelling spectroscopy. A Kondo temperature of 124 (140) K on the Cu (DCA) sites is determined from fitting temperature dependent measurements. These observations are consistent with supporting DFT+U calculations. Our work paves the way for atomically precise, meso-scaled 2D metal-organic frameworks for strongly correlated electronics.
About the presenter
Dhaneesh Kumar Gopalakrishnan is an PhD student working with Dr Agustin Schiffrin at Monash University. Within FLEET’s research theme 1 and Enabling technology theme A, Dhaneesh synthesises and characterises 2D organic-based materials, searching for those that exhibit topological electronic properties. Synthesis and characterisation of these materials are carried out in the state-of-the-art scanning probe microscopy set-up in the Schiffrin lab, enabling precise engineering and probing of these materials down to the atomic scale.